This invention is directed to an electronic timepiece control circuit, and in particular to electronic timepiece control circuit for cyclically disposing in sequence a timekeeping circuit into at least three timekeeping functional modes, and that is further adapted to automatically return the timekeeping circuit to a predetermined timekeeping functional mode.
The development of highly accurate, multi-functional electronic wristwatches has been due, in large measure, to improvements in integrated circuit techniques, and improvements in electro-optical displays. Such improvements have resulted in electronic wristwatches that can not only provide a display of hour, minute, second, month, date and day of the week information, but can also function as a stopwatch or operate as a global chronometer. Although the number of functions performed by wristwatches continues to increase, efforts have been made to not increase the number of control switches utilized to select the functional modes of the electronic wristwatch and, additionally, to control the functions once the functional modes have been selected. In order to limit to three the number of switches required to select the different functions to be performed by the wristwatch and control the performance of the functions selected, mode select circuitry that sequentially selects each of the functional modes, in a cyclical manner when at least three timekeeping functions are provided, have been utilized.
For example, in a multi-functional wristwatch incorporating certain of the functions detailed above, the timekeeping circuit of the wristwatch is cyclically disposed into at least four different timekeeping functional modes including an hour-minute-second functional mode.fwdarw.a month-date-day of the week functional mode.fwdarw.a stopwatch functional mode.fwdarw.time correction for hours-minutes-seconds functional mode.fwdarw.correction for month-date-day of the week functional mode and, thereafter, a return to the hour-minute-second functional mode in response to each operation of a functional mode selection switch. Once a specific timekeeping functional mode is selected, at least one timekeeping function (such as measuring elapsed time when the timepiece is in a stopwatch mode) is performed. However, one disadvantage of cyclically disposing the timekeeping circuitry in each of the functional modes is that once the particular functional mode is selected, such as a stopwatch mode, the wristwatch cannot be returned to a preferred mode of operation, such as the hour-minutes and seconds functional mode without selecting each of the remaining functional modes in the sequence. Accordingly, for the timepiece detailed above, the mode select switch must be actuated three additional times in order to return the wristwatch to the preferred functional mode wherein hour-minute-second timekeeping information is displayed. Electronic wristwatch control circuitry that is adapted to cyclically dispose, in sequence, the timekeeping circuitry in each timekeeping functional mode and is further adapted to automatically return the timekeeping circuitry to a predetermined functional mode would overcome the disadvantage noted above.